Lightning struck Kolkata 400 times in 2 hours yesterday reports weather office

Kolkata witnessed an extraordinary spell of severe weather as a rare multicell thunderstorm triggered nearly 400 lightning strikes within a span of two hours, according to preliminary scientific assessments. The intense storm, accompanied by torrential rain, frequent lightning, and strong winds, struck the city for the second time within 24 hours. Meteorologists stated that the event differed from a typical Kalbaishakhi (Nor'wester), identifying it instead as a multicell thunderstorm that spread lightning activity across a wide geographical area. Experts added that the actual number of lightning strikes could exceed 400 after complete regional data is compiled through radio signal-based lightning detection systems.

Weather expert Ramkrishna Datta explained that multicell thunderstorms differ from supercell storms in both structure and impact. While supercell storms are generally more destructive within a limited area, multicell storms generate widespread lightning and thunder across a much larger region. Meteorologists reported that unstable atmospheric conditions extended beyond Kolkata, simultaneously affecting North Bengal, South Bengal, and large parts of Bangladesh. High humidity, an active monsoon system, a low-pressure area, and light surface winds contributed to the rapid formation of cumulonimbus clouds reaching heights of approximately 12 to 14 kilometres, resulting in nearly 100 mm of rainfall within two hours. Scientists stated that the storm registered a Bulk Richardson Number of 125, confirming it as a multicell weather system.

Researchers also highlighted environmental factors contributing to the increasing frequency of lightning activity. S.D. Pawar of the Indian Institute of Tropical Meteorology stated that rising air pollution, higher concentrations of dust and fine particulate matter, increasing urban temperatures, and continuous moisture inflow from the Bay of Bengal are creating favourable conditions for intense thunderstorm development. Scientists noted that the probability of lightning increases significantly with every 1°C rise in global temperature. In view of the prevailing conditions, the Meteorological Department has advised people to avoid open fields, isolated trees, and electric poles during thunderstorms.